FORT MYERS, Fla. -- Known throughout his career for his speed and defense, Byron Buxton came out of nowhere to finish tied for second on the Twins in homers (13) last season. This spring, he actually looks the part.

It's so common for players to arrive at Spring Training camps with optimism regarding their physique that the phrase "in the best shape of his life" tends to become a punchline this time of year. Even in that context, Buxton is turning heads.

"Physically watching Buck walk into the ballpark was kind of a ... it was a 'wow' moment in a lot of ways," manager Rocco Baldelli said. "I mean, he's obviously a great athlete and we know him very well. We know what we're getting physically and with the things he can do. But you know, seeing him come in after putting on, you know, 10 or 15 pounds of -- I mean, there's just muscle there."

The skinny speedster who debuted in 2015 has been replaced by a filled-out, muscular frame over the past three seasons. Before the '19 season, Buxton arrived in camp having added 21 pounds of muscle in an effort to better cushion his body from the impact of collisions with the outfield wall.

Buxton only appeared in 39 games last season as he dealt with aggravation of his surgically repaired left shoulder and a hit-by-pitch in the helmet, and though neither injury was the direct result of a collision, the added muscle should only help that durability. Perhaps it will also help him continue the power show that included five homers in August and eight in September, coupled with the best hard-hit rate (47.9%) and average exit velocity (91.2 mph) of his career.

As for concerns that all that muscle could slow Buxton down? Don't worry about that.

"I know he also spent a lot of time with his track coach back home," Baldelli said. "It wasn't just putting on size and leaving it at that. He spent the offseason really, really working to help better himself. And it was obvious when he walked in the door."

Smeltzer to start Grapefruit League opener
Baldelli announced on Thursday that left-hander Devin Smeltzer will be first on the mound for the Twins when they open their modified Grapefruit League schedule against the Red Sox on Sunday at Hammond Stadium at 12:05 p.m. CT. The club has not yet announced who else will be joining the 25-year-old on the mound.

Smeltzer last faced live hitters on Tuesday -- the first day of full-squad workouts -- when he pitched against a group of teammates that included Josh Donaldson, Jorge Polanco, Willians Astudillo, Miguel Sanó, Brent Rooker and JT Riddle.

According to the 2021 operations manual, games through March 13 will be scheduled as seven-inning games, but they can be shortened to five or lengthened to nine innings upon agreement of both managers. Any subsequent spring games will be scheduled as nine-inning games but can similarly be shortened to seven innings.

Riddle manning shortstop in Simmons' absence
The Twins are in a bit of a bind at shortstop early in camp due to Andrelton Simmons' continuing visa issues in Curaçao and top prospect Royce Lewis' impending surgery to repair his torn ACL. In their absence, the club has been using non-roster invitee Riddle as its primary shortstop in defensive drills with the Major League players.

Minnesota has a handful of other options in camp, including prospect Nick Gordon and non-roster invitees Tzu-Wei Lin and Andrew Romine, but Riddle's defensive prowess has made him the preferred player of the group, Baldelli said. Riddle, 29, played every infield and outfield position for Pittsburgh last season, and he has a career .616 OPS with the Pirates and Marlins.

"Watching him throw, it’s pretty impressive," Baldelli said. "He doesn’t have to work very hard to get the ball across the infield in a hurry, and it’s something that kind of sticks out when you watch him make plays. He’s a guy that we still think has some offensive upside, but looking at what he can do at shortstop is certainly something that stuck out to us.”